Adapter for vacuum-tube sockets



July 14, 1925. 1,546,161

M.ALDEN ADAPTER FOR VACUUM .TUBE SOCKETS Filed D96. 29, 1923 INVENTOR, JZZQ%%.%ZZQ

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Patented July 14, 1925.

UNITED STATES PATENT OFFICE.

MILTON ALDEN, OF SPRINGFIELD, MASSACHUSETTS, ASSIGNOR TO ALDEN MANU- FACTURING 60., OF SPRINGFIELD, MASSACHUSETTS, A CORPORATION OF MASSA- CHUSETTS;

ADAPTER FOR VACUUM-TUBE SOCKETS.

' Application filed December 29, 1923. Serial No. 683,487.

To all whom it may concern:

Be it known that I, MILTON ALDEN, a citizen of the United States of America, residing at Springfield, county of Hampden, Commonwealth of Massachusetts, have invented certain new and useful Improvements in Adapters for Vacuum-Tube Sockets, of wliich the following is a specification.

This invention relates to improvements in socket devices for retaining and holding a small size vacuum tube for use in a wirelessoutfit.

Particularly it relates to an attachment or what is sometimes termed an. adapter, that is designed to be readily inserted into and removed from a larger or standard size vacuum tube receiving socket, whereby a tube of different or smaller diameter than the standard size may be electrically connected to the larger socket, and without changing any of the electrical connections.

Broadly it comprises a cylindrical shaped hollow member, the outside diameter of which is substantially equal to the inside diameter of the standard vacuum tube receiving socket. It is provided with four electrical terminals, or prongs, that engage the same terminals .of the standard socket that the terminals of a large vacuum tube engages. Within the bottom portion of the adapter are placed four spring mounted contact members with which the four terminals of the small size vacuum tube engage. The internal diameter of this adapter is equal to the outside diameter of the smaller vacuum tube. By means of this construction a wireless outfit may be used with either the larger or smaller sized tubes. Provision is made for reducing to a minimum capacity effects by providing the adapter with electrical connections-that do not run parallel with each other.

Referring to the drawings: Fig. 1 shows the adapter as being vertically removed from the standard size socket. Fig. 2 is a vertical sectional vlew on the line 2-2 of Fig. 3 showing two of the depending terminals of the adapter which are embedded in the molded material of the base portion thereof and the terminalsbn buttons on the inside of the adapter which are electrically connected to the dependlng terminals and with which the terminals of,

the tube engage.

Fig. 3 is a top plan view of Fig. 1 showmg the four internally located spring mounted button terminals.

Fig. his a horizontal sectional plan view on the line H of Fig. 1 showing in full lines the four button terminals indicated in Fig. 3 and in dotted lines the electrical connections between the button terminals and depending terminals or prongs that proect below the outer bottom surface of the adapter. g

. Fig. 5 is an exterior bottom plan view of F igs. 1, 2, and 3 showing the four downwardly projecting terminals or prongs and the electrical connections embedded in the bottom part and connecting the spring actuated button terminals on the inside of the adapter with the downwardly projecting terminals, and

Fig. 6-is an enlarged detail sectional View on the line 6;6 of Fig. 4 showing the inner end of one of the downwardly projecting terminals embedded in the base of'the adapter, the spring mounted button terminal on the inside of the adapter and the embedded electrical connection between the two terminals. 7

Referring to the drawings in detail:

1 designates the standard form and size of vacuum tube receiving socket having the usual lamp engaging contact terminals located therein; two of which are shown in dotted lines at 2 and 3. This form of socket constitutes the subject matter of my pending application for United States Letters Patent Serial No. 621,57 5 filed February 27, 1923. The adapter as a whole isdesigned by the reference nluneral 4. It is formed with a bayonet joint socket connection 5 for receiving the small vacuum tube partially indicated in Fig. 2 in dotted lines, by the reference numeral 5. This tube is com mercially desi iated by the characters VV199, or 299 or sometimes by the name peanut tube. Projecting-from the lower surface of the bottom part of the adapter are four depending terminals 6, 7, 8, and 9. An'enlarged detail View of one of hese terminals is shown in Fig. 6. Fixedly secured to each of these terminals is a metallic plate 10",,which is embedded in the bottom part of the molded insulating material of the adapter as shown in Figs. 2 and G. The bottom part 4 of the adapter is formed with openings 11 in each one of which is located the coiled spring 12 and passingthrough this spring is the depending part 12 which is formed as an integral part of the spring mounted button 13 which is located in the larger opening 11. The spring 12 therefore forms a good electrical connection between the button 13 and the metallic plate 10. The headed over or cone shaped lower end portion 14 of the depending part 12 prevents this part from being forced upward and through the opening 11 by the expansive force of the spring 12. The part 12 moves downward when the button 13 is depressed upon the insertion of the tube 5. 'The four metallic strips or plates 10 (see Figs. 4 and 5) form an electrical connection between the four depending terminals 6, 7, 8, and 9 and the four spring mounted contact buttons 18. The angular relation or arrangement of these connections 10 between the several exteriorly located depending terminals 6, 7, 8, and 9 and the interiorly located contact buttons 13 is such that the depending terminals or contact prongs 5 on the small vacuum tube 5 will be electrically connected to the correct poles of the batteries. 1 That. is to say, if the wires from the batteries are correctly connected to the terminals 1 of the large socket 1, the batteries will be correctly connected to the four terminals 5 of the smaller vacuum tube 5. The relative arrangement of the terminals 6, 7, 8, and 9 (which make electrical contact with the contact strips 2, 3, etc., in the socket 1) and the several button contacts 13 is clearly indicated in Figs. 4 and 5. Fig. (Sclearly shows on an enlarged scale, the construction of one of the connections between a terminal 19, and a plunger 13.

By arranging the connecting plates 10 so that they do not run parallel with each other and making these plates of short length and with their edges opposed to each other practically all possibility of capacity effects of any consequence are prevented between these plates, which would rob these tubes of much of their efficiency. Another reason of preventing the formation of any capacity effects is that the plates 10 contain only a very small volume of metal, and therefore a small area of surface on which any charge can be retained. An important feature is the arrangement of the plates 10 with their edges opposed to each other instead of placing their side surfaces; their edges therefore presents very much less surface than the sides.

The adapter constmction therefore provides means for making electrical connections with all of the four contact plates in the larger socket of standard size, only two of these plates are indicated at 2 and 3. The construction therefore provides means whereby the positive and negative battery terminal connections to the socket 1 may be correctly maintained when the vacuum tube 5 is inserted in the adapter 4 thereby avoiding any possibility of the tube 5 being injured from wrong battery connections or preventing the device from being inoperative. It is understood that the positive and negative terminals of the batteries are correctly indicated on the socket 1. They are usually placed adjacent the binding posts 1. Formed on the outer surface of the adapter are a series of parallel concave grooves 15 as shown in Figs. 1, 4, and 5. These grooves are for design purposes only and have no other particular purpose except in the saving of material. The plate portions 10 are secured in the bottom 4 of the insulating material during the molding and vulcanizing process and the upper ends of the terminals 6, 7, 8, and 9 are formed with serrated or roughened surfaces 16, thus preventing these terminals from loosening and at the same time serving to rigidly retain the plates 10 in place. The small vacuum tube 5' is retained in the adapter 4 by means of the pin 17 which engages the shoulder of the bayonet groove 18. The springs 12 beneath the contact buttons 13 operate to retain the pin 17 in the groove 18 in thewell known manner.

l/Vhat I claim is: 4

1. A device for the purpose described, comprising a recessed member to receive the base part of a tube, with a bottom part hav ing. a plurality of rigid or immovable electrical contact terminals depending from the outer surface of the bottom, a plurality of spring actuated movable contact terminals within the recessed part of the member and electrical strip means for severally and directly connecting the rigid and movable terminals, the said movable terminals passing through openings in the strip means.

2. An adapter device comprising a hollow member formed with a bottom and having a plurality of terminals which are rigidly secured to the bottom which are exteriorly located and depending from the bottom thereof, a plurality ofinteriorly located movable terminals within the member, plate means for severally and electrically connecting the two sets of terminals including button contacts located in an opening of the bottom, the intcriorly located buttons having a depending part, a spring interposed be tween the depending part of the said terminals and the said plate means and normally retaining these terminals in an elc- I 'vated position but permitting them to be depressed by the contact terminals on a vacuum tube when the tube is inserted within the hollow member.

3. An adapter device comprising a member with a closed end, extcriorly located terminals on the closed end, contact button ter- .nals upward but permitting them to be pushed downward when inserted.

4. Two electrical contact devices comprising a depending prong member and a spring mounted button-like contact member, a plate electrically connected to the prong member and the button member and formed with an opening to receive the said button member, and a spring interposed between the plate and the said button member.

5. Two electrical contact devices comprising a depending prong member and a spring a vacuum tube is mounted button-like contact member, a plate electrically connected to the prong member and the button member and formed with an opening to receive the said button member, and a spring interposed between the plate and the said button member, the upper end of the prong member being serrated for retaining the same embedded in the material of the molded insulating material of the member.

6. In an adapter, the combination with a vacuum tube receiving member formed with a bottom part, of a plurality of rigid depending contact prong members, a plurality of contact button members oppositely located from the rigid depending contact members for engagement with the contact terminals of the tube when inserted, a plurality of plates in the lower side of the bottom part for severally and electrically connecting the plurality of rigid depending and button contact members, said plates being arranged in the same plane with reference to each other to obviate or lessen the formation of capacity effects thereon.

7 In an adapter the combination with a vacuum tube receiving member, of a plurality of dependin contact members, a plurality of contact uttons located in openings in the adapter and oppositely located from the depending contact members for engagement with the contact terminals of the tube when inserted, a plurality of plates for severally and electrically connecting the plurality of depending and button contact members, said plates being arranged with reference to each other to obviate or lessen the formation of capacity efi'ects thereon, and a spring in the openings and interposed between each of the plates and the contact buttons.

8. A contact device for an adapter comprising a contact button member formed with a reduced part, a plate formed with an opening to receive the reduced part, a spring encircling the reduced part and located between the button member and the plate and the reduced part being headed over to prevent the spring from withdrawing the button member from the plate but permitting it to move in the opening when a vacuum tube is inserted in the adapter.

-9. A contact device for an adapter comprising a contact button member formed with a reduced part, a plate formed with an opening to receive the reduced part, a spring encircling the reduced part, and located between the button member and the plate and the reduced part being headed over to prevent the spring from withdrawing the button member from the plate but permitting it to move in the opening when a vacuum tube is inserted in the adapter, a contact member depending from the adapter for engagement with the contact-terminals of a socket member and connected to the plate.

10. An. adapter device for insertion into a vacuum tube socket member comprising, in combination, a single recessed member having a bottom part, contact terminals located on the opposite sides of the bottom part of the recessed member, plates on the lower side of the bottom part for electrically connecting the opposite-1y located terminals and arranged at angles to each other for preventing the formation of capacity effects on the plates.

11. An adapter device for insertion into a socket member comprising, in combination, a single recessed member having a bottom part, contact terminals located on the opposite sides of the bottom part of the recessed member, plates for electrically connecting the oppositely located terminals and so arranged with relation to each other for preventing the action of capacity effects on the plates and said lates being embedded in the material of the bottom part of the device.

12. An'adapter device for insertion into a socket member comprising, in comb-ination a single recessed member having abottom part, contact terminals located on the opposite sides of the bottom part .of the recessed member, plates arrangedwith their edges opposed to each other for electrically connecting the opposite] located terminals and so arranged with rel ation to each other for reventing the action of capacity effects on t 1e plates and said plates being embedded in the material of the bottom part of th device MILTON ALDEN. 

